Dramatic changes in muscle contractile and structural properties after 2 botulinum toxin injections. Issue 4 (30th June 2015)

• Record Type: Journal Article
• Authors: Minamoto, Viviane B.; Suzuki, Kentaro P.; Bremner, Shannon N.; Lieber, Richard L.; Ward, Samuel R.
• Is Part Of: Muscle & nerve. Volume 52:Issue 4(2015:Oct.)
• Page Start: 649
• Page End: 657
• Publication Date: 2015-06-30
• Subjects: Neuromuscular diseases -- Periodicals; Muscles -- Periodicals; Nerves -- Periodicals; 616.74
• DOI: 10.1002/mus.24576
• Languages: English
• ISSNs: 0148-639X

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p> <italic>Introduction</italic>: Botulinum toxin is frequently administered serially to maintain therapeutic muscle paralysis, but the effect of repeated doses on muscle function are largely unknown. This study characterized the muscle response to 2 onabotulinum toxin (BoNT) injections separated by 3 months. <italic>Methods</italic>: Animal subjects received a single toxin injection (n = 8), 2 BoNT injections separated by 3 months (n = 14), or 1 BoNT and 1 saline injection separated by 3 months (n = 8). <italic>Results</italic>: The functional effect of 2 serial injections was exponentially greater than the effect of a single injection. While both groups treated with a single BoNT injection had decreased torque in the injected leg by approximately 50% relative to contralateral legs, the double BoNT injected group had decreased torque by over 95% relative to the preinjection level. Both single and double BoNT injections produced clear signs of fiber‐type grouping. <italic>Conclusions</italic>: These experiments demonstrate a disproportionately greater effect of repeated BoNT injections. <italic>Muscle Nerve</italic> 52: 649–657, 2015</p> </abstract>